Freelance work is on the rise, according to the Bureau of Labor Statistics, which reports more than 15.5 million people in the United States are self-employed and working independent contractors. The Bureau anticipates that by 2020 more than 40 percent of American workers (60 million people) will follow suit. Workers across the country are leaving and even turning down corporate jobs to become entrepreneurs.

So what exactly has these professionals shifting gears from working at corporations to working for themselves? A Harvard Business Review report from 2012 cites growing employee dissatisfaction and the removal of barriers that once made independent contracting challenging. New online marketplaces are making it easier for consultants to find work. Additionally, contractors are finding jobs that permit them to work remotely—opening them up to a broader range of opportunities. Plus, companies are seeking contractors with competitively priced fees for services.

The rise of co-working spaces has also proven to be a catalyst for freelancing. Contractors are turning to co-working spaces like WeWork for office spaces and small business development resources.